Sylvia J. Shaw

Association of HLA-DPB1*0301 With IDDM in Mexican-Americans

Susceptibility to IDDM has been associated with specific alleles at the HLA class II loci in a variety of human populations. Previous studies among Mexican-Americans, a group ancestrally derived from Native Americans and Hispanic whites, showed that the DR4 haplotypes (DRB1*0405-DQB1*0302 and DRB1*0402-DQB1*0302) and the DR3 haplotype (DRB1*0301-DQB1*0201) were increased among patients and suggested a role for both DR and DQ alleles in susceptibility and resistance. Based on the analysis of 42 Mexican-American IDDM families and ethnically matched control subjects by polymerase chain reaction/sequence-specific oligonucleotide probe typing, we report an association of IDDM with the DPB1 allele, *0301 (relative risk = 6.6; P = 0.0012) in this population. The analysis of linkage disequilibrium patterns in this population indicates that the observed increased frequency in DPB1*0301 among patients cannot be attributed simply to linkage disequilibrium with high-risk DR-DQ haplotypes. These data suggest that in addition to alleles at the DRB1 and DQB1 loci, polymorphism at the DPB1 locus may also influence IDDM risk.

Gallbladder dysfunction in diabetes mellitus

To further elucidate the mechanism of impaired gallbladder emptying in diabetics with and without neuropathy, gallbladder function was assessed by ultrasonography following a medium-chain triglyceride (lipomul, 1.5 mg/kg) infusion into the duodenum and compared to that during intravenous infusion of cholecystokinin in diabetic women. Results were compared with five healthy control women. Mean (±sd) maximal percent gallbladder volume in diabetics following lipomul was reduced to 49±8% and after intravenous cholecystokinin to 47±9%, which was less than those in controls, 21±9% and 24±6%, respectively, but not significantly different. Further analysis of gallbladder emptying to lipomul differentiated two subgroups of diabetics: one subgroup (N=5) had emptying comparable to controls (responders), while the other (N=5) had very modest emptying (nonresponders). Two of the patients in the latter group had normal gallbladder emptying during exogenous cholecystokinin and their response would be compatible with visceral neuropathy. Blood levels of cholecystokinin, measured by bioassay, following lipomul and exogenous cholecystokinin were similar in controls and diabetics. Presence of diabetic neuropathy did not correlate with impaired gallbladder emptying. Follow up at 6 and 12 months of the three nonresponder diabetics revealed that no gallstones had developed and that two of them became responders to exogenous cholecystokinin. We conclude that: (1) following lipomul, about 50% of diabetics in this study have impaired gallbladder emptying, which is not strictly correlated with diabetic neuropathy; (2) this was not due to abnormal cholecystokinin release; (3) in diabetic patients with impaired gallbladder emptying another abnormality may be present in the gallbladder; and (4) impaired gallbladder contraction may not lead to gallstone formation in one-year follow-up.

Amenorrhea, pregnancy, and pregnancy outcomes in women following spinal cord injury: a retrospective cross-sectional study.

OBJECTIVE To assess the prevalence of amenorrhea and pregnancy as well as pregnancy outcomes following spinal cord injury (SCI) in women. METHODS In this retrospective cross-sectional study, women with SCI were interviewed regarding demographic data, details about the timing and type of SCI they sustained, whether the neurologic deficit was complete or incomplete, and reproductive history. The study was initiated in September 2001 and lasted 3 years. Measures were compared for significance with the level of injury and extent of neurologic deficit using descriptive statistics, analysis of variance, and 2-tailed t tests. RESULTS Of 128 women, 53 (41.4%) had postinjury amenorrhea. The amenorrhea was transient in 50 of 53 women. SCI occurred at the mean (+/- SD) age of 27 +/- 9 years. In this group the lesions were at thoracic spine in 35 (66%), cervical spine in 16 (30%), and lumbar spine in 2 (4%). Neurologic deficit was complete in 31 women (58%) and incomplete in 22 (42%). The occurrence of amenorrhea was not influenced by the extent of neurologic deficit. Of 50 women who experienced transient amenorrhea, 10 (20%) became pregnant (6 livebirths, 4 elective terminations). Mean duration of amenorrhea was 7.96 +/- 10.9 months; there was no significant difference between mean duration of amenorrhea in women who got pregnant vs those who did not (6.4 +/- 3.8 months vs 15.8 +/- 30.8 months; P = .34). Pregnancy rate was significantly higher among those who sustained injury at a younger age (21.6 +/- 5.3 years vs 28.3 +/- 9.3 years; P = .033). CONCLUSIONS Level of injury did not influence duration of amenorrhea or occurrence of pregnancy. Women who experience transient amenorrhea after SCI may achieve successful pregnancies.

Polymorphic Gene Markers in Mexican-Americans Residing in Southern California

The gene frequencies of nine different genetic polymorphic markers [ABO, MNS and P blood groups; haptoglobin, transferrin, Gc protein, complement (C3), properdin factor B and alpha 1-antitrypsin] were determined in 94 Mexican-Americans residing in the Los Angeles, California area. Comparisons with published data on Mexican-Americans living in other areas of the United States or in Mexico itself revealed no significant differences in the gene frequencies between this and previous studies. However, data from the current study demonstrated significant differences in ABO and haptoglobin allele frequencies compared to published non-Hispanic Caucasian data. These data suggest a large degree of genetic homogeneity in the Mexican-American population residing in the United States. Additional gene marker studies will be important to test this hypothesis and further define the degree of non-Hispanic Caucasian admixture in this population.

Hypoglycemia Reported in Patient Safety Network (PSN)

Hypoglycemia (hG) affects up to 26% of inpatients with diabetes mellitus (DM) and is responsible for an increase in cardiovascular morbidity and mortality. The goal of this pilot project (PP) was to decrease inpatient hG.